Cumin
by idioticonion
Summary: Billy's Transmatter Ray goes a little bit wrong, and brings our favourite playboy into his universe. Set pre Act I - Warning! This contains M/M slash and PWP!


**Cumin**

Barney staggers and almost falls, choking on the billows of dust that surround him, desperately trying to shield his ears from the wailing siren. For a moment, he's disorientated, sure that terrorists must have attacked the GNB building. Only a moment before he was in his office, about to have "lunch" with (on) his secretary and now…

He opens his eyes and blinks away the grit. He's in a room, a small room with whitewashed walls and a workbench with a bunch of glass bowls and test tubes, like a freakin' crystal meth lab or something. Drugs? That would explain why he appears to be face-to-face with…

Himself.

Barney blinks. Slowly, he steps to the side as the wailing nose fades away. His doppelganger moves also, mirroring him. His doppelganger is wearing some kind of fancy-dress costume and the most goddamn stupid expression he's ever seen. His doppelganger's eye starts twitching.

What the f-?

Now, Barney's a lot smarter than most people give him credit for. His mind rattles through the various possible permutations, the various options and he comes up with one single answer, one most probable outcome.

"Long lost twin, high five!" He says, raising his hand.

His doppelganger looks utterly confused. Barney worries for a moment that he's dumb, despite the white lab coat and goggles. Perhaps he got all the brains in the family.

"Hello?" Barney said, lowering his hand. "Earth to Bro? My name's Barney? Who're you, dude?"

The other guy blinks rapidly, then swallows. "I'm… I'm Billy. Um… that is, Doctor Horrible!" He speaks the name as if it's got capital letters, Barney notes.

Great. His twin brother is a nerd.

"Okay… so I'll assume you're on your way to some kind of… geek convention… under the vague hope that you actually have one ounce of awesome running through those veins…" He mutters. "Billy?"

Billy nodded. The guy is so _pasty_. Has he never heard of the spray-on-tan? But even so… there's those blue eyes, the spiked, blonde hair and, beneath that outsized costume (he hopes) a body to die for. It's like looking in a mirror.

Where the most awesome guy he's ever met lives.

Barney can't help himself. He moves in close to Billy, lifting the goggles from his forehead, fingers tracing the divits left in his flesh. His skin is grubby around the marks, like he's been wearing those things for days.

Billy quivers under his touch, lips parted, eyes wide. "What're you… doing?" He asks.

That voice… God, it's _his_ voice. Billy's got his voice. Barney feels something, his heartbeat, his pulse, begin to throb steadily through him. He takes another stop closer until they are chest to chest. "Wow… what _are_ you…?"

Billy swallows, his Adam's apple bobbing. "I'm a… scientist. I was… experimenting… with a new… it's called the Transmatter Ray…" More capitals. "It transports things from one place to another, one dimension to another, across space and time…"

Barney laughs. "Right…" His fingers trail across Billy's face, tracing the line of his chiselled cheekbones, across the stubble covering his jaw. "Right, because you're a scientist…"

"What are you?" Billy asks, incredulously. "You look exactly like me… yet you're not me?"

Barney laughs. "I'm the upgrade, baby!" He grins, wolfishly, his hand moving around the back of Billy's skull, thumb brushing through the short, soft tufts of hair. "I'm your worst nightmare…" And he leans in, pressing his mouth hard against Billy's, holding him in an iron grip until he feels the other man tense. He slips his tongue between Billy's lips, encouraging him to open his mouth, his other hand popping one of the buttons of the labcoat. When he pulls away, Billy seems to sag in his arms and he staggers back, his eyes very wide, very confused, very _innocent_.

Wow. Not only a geek, but a virgin too?

Barney can't decide if this is the hottest thing ever or just the saddest thing he can imagine. But her knows, beyond a doubt, that this might be the only chance he'll get to cross off _himself_ off his list. The list of all the people he'd really love to fuck.

"You've never done this…" He says, letting Billy back away.

"Not with- No… I- I-… No!" Billy shakes his head, biting his lip. The other man's brow crinkles in that adorable way that is has taken Barney hours in front of the mirror to perfect.

"Do you want to…?" Barney leers. He doesn't approach Billy now, just hooks a finger under his tie, loosening it. "I can make you feel… incredible…" His eyes never leave Billy's, hoping that this guy, his brother, has an ounce of the Stinson libido. He quickly unbuttons himself, revealing his hard abs, his flat stomach.

"You're- I don't know what you are…" Billy says, helplessly. "Penny-"

"You've got a girl?" Barney says with a laugh… "Wow... Dude, you really think she's gonna want you if you're no good in the sack?"

"How do you know that-?"

"I can tell from a mile away…" Barney lets his shirt fall from his shoulders. "So can she…"

"Penny…?" Billy breathes, then looks away. "No, this is ridiculous. You're… you're an aberration. A mistake in the formula, that's all. This is _not_ happening…"

"This is totally happening, so man up. You want to come harder than you ever have? Or do you wanna be a pussy about it?" Barney sneers and in two steps he's backing Billy up against the wall and kissing him again, this time holding nothing back. Their teeth clash as Billy struggles against him, but as soon as Barney shoves one hand down Billy's trousers, fingers massaging his groin, all Billy's resistance seems to crumble away.

"Oh… oh…" Billy gasps as Barney whips his hand away and grinds his own groin against Billy's.

"See?" Barney says, chuckling, running his tongue across the Billy's lips, flicking the tip over the corner of his mouth. "Feel it?"

"I feel it…" Billy's voice is hoarse, his hands running clumsily over Barney's back.

"Then get that coat off…" Barney demands. To his great delight, Billy hurriedly unbuttons his coat, letting it fall open revealing that he's wearing jeans and an over-sized tshirt.

"And those will have to go too…" Barney laughs.

The labcoat quickly falls to the floor in a heap, followed by the tshirt.

"So that's what I'd look like, even without all those hours in the gym…" Barney mutters. "Awesome!" He laughs at Billy's expression, rubbing one finger over one nipple until it hardens under his touch. "You got a bed, Billy?" He asks.

Billy looks over his shoulder at what looks like a solid wall. Barney lets him go for a moment, long enough for his doppelganger to spin a large, metal wheel which moves the entire wall, revealing a modest, if slightly untidy, apartment beyond.

"Heh… okay, that's…"

Then Billy's taking his hand and practically dragging him through into the bedroom (the loosest example of the word he's ever known) and down onto the tiny bed. Billy loses his balance, falling heavily onto the mattress. Barney's on him in an instant, pulling at the zipper of his jeans and yanking them down over his hips. He's gratified to see a very familiar erection spring free of his underwear.

"Hello! Now _this_ is pretty weird…" He mumbles, unable to resist having a taste. Running his tongue along the shaft, he pins Billy to the bed with both hands. "Always wanted to do that," He murmurs, lips brushing against the warm, velvety flesh. It tastes so familiar that it's… freaky…

Billy lets out a little cry as Barney takes the tip of his dick into his mouth. He wants to make Billy moan, make him beg. He wants, more than anything else, to fuck him. He lets his dick slide from his mouth.

"Hey…" He grins. "You got anything we can use as lube in that lab of yours?"

Billy smiles shyly. "I've got _lubricant_… Never thought I'd use it for t-this!" The last word becomes a squeak as Barney circles the head of his cock with his tongue.

"Well?" He demands.

Billy leans over the side of the bed, rummaging underneath while Barney strips off his own pants then pounces on his chest, his tongue flicking rapidly across his nipples.

"Hey… stop that! It's… _really_ distracting, dude!" Billy says and Barney flashes him a devilish grin as his doppelganger produces a plastic tub. "Lube?" He says.

Barney takes the tub, fishing a condom out of his back pocket, causing Billy's eyes to practically bug out of his head. "Hey… relax!" Barney says.

"'m not scared…" Billy replies, his expression indicating otherwise.

"Whatever…" Barney laughs, sheathing is dick in latest and coating it liberally with the sticky, clear substance. "Whoa, what _is_ this stuff?" He asks.

"It's… experimental…" Billy grins as Barney rolls him onto his front. _Nice buns_, he thinks, giving them a squeeze.

"Billy Stinson…" Barney says, his fingers delving between Billy's buttocks. "With a little help, you could be pant-meltingly awesome."

Billy groans, the tenses as Barney's fingers slide inside him, forcing their way into the tight warmth. He presses his lips against Billy's shoulder blade, lining himself up until he can push his dick into Billy, not gently, lust overtaking him at the though of fucking him, of fucking _himself_… His eyes roll back in his head because Billy is so, so tight, the pressure is so intense and this is so much better than the tightest pussy he's ever had. Yeah… this is what he needs, this is _it_…

Billy yelps beneath him as he hammers into his prostate, his body bucking and writhing until Barney has to grin his teeth and squeeze his eyes shut just to keep control. It's only a few minutes (not long enough, not long at all) until he comes, hard and fast, shooting his load into the condom, almost wishing he'd gone bareback because he just doesn't _care_ about the consequences in that instant, he just wants to be inside Billy…

Barney rolls off him, his heart hammering in his chest. Billy just lies there, wheezing, his torso covered in a sheen of perspiration. God, he looks hot.

"You look… hot…" Barney says out loud. Sheesh that sounds lame.

Billy turns on to his side. God, his eyes are so blue. He's _gorgeous_…

"You too," Billy says. "I just hope you don't turn into cumin in the morning…"

"Cumin?" Barney asks, and rubs his eyes. He's tired suddenly and everything's blurry. "What're you-"

Then there's a flash, and a siren, so high-pitched that it makes his skull ache, his ears bleed, his eyeballs expand… and suddenly he's on the floor on his knees and he's birthday suited up and freezing cold and…

Holy crap…

He opens his eyes to find blood dripping out of his nose. He's staring at the floor of his own office. He swallows.

And, weirdly, it does taste kind-of like cumin.


End file.
